Brainteaser Interview Questions

A brainteaser is a form of puzzle that requires thinking in unconventional ways with given constraints in mind; sometimes it also involves lateral thinking. On a general scale, the most obvious answers are almost always the incorrect ones.

Sample Brainteaser Interview Questions

Q1 − You’re in a room with three light switches, each of which controls one of the three light bulbs in the next room. Find out which switch controls which bulb. All lights are initially off, and you cannot see into one room from the other. You can check the room only once. How can you determine which switch is connected to which light bulb?

Q2 − Here's a mobile phone. Deconstruct it for me.

Q3 − An apple costs 40 cents, a banana costs 60 cents, and a grapefruit costs 80 cents. How much does a pear cost?

Q4 − Describe the Internet to someone who woke up from a 30-year coma.

Q5 − A scientist puts a bacteria in a petri dish at exactly noon. Every minute, the bacteria divides into two. At exactly 1 pm, the petri dish is full. At what time was the dish half full?

Q6 − Is it better to be perfect and late, or good and on time?

Q7 − "Who is the smartest person you know personally? Why?"

Q8 − You wake up early one morning and find the light in your bedroom is broke. You get dressed in the dark. Your drawer has socks of three different colors: red, yellow, and blue. How many socks do you have to take out to be certain of having a matching pair?

Q9 − Why are manhole covers round and not square?

Q10 − You are blindfolded and sit in front of a table. On the table are many coins, 10 of which have heads facing up. How do you split the group of coins into two groups such that the same number of coins are heads-up in each group? You don’t know how many coins there are and you can’t tell which side is facing up in any way.